Pressure to improye quality and lower cost of health care has stimulated the evaluation of the effectiveness of medical interventions, such as gastrointestinal (GI) endoscopy. Despite widespread use of endoscopy in the diagnosis and treatment of GI diseases, very little is known about the utilization and effectiveness in community-based settings. The Clinical Outcomes Research Initiative (CORI) built a consortium of physicians who contribute data to a national endoscopic data repository to study outcomes of endoscopic procedures in diverse practice settings. These data have been used to study endoscopic utilization, frequency and severity of endoscopic findings, outcomes of endoscopic treatment, impact of endoscopy on quality of life and heath care utilization, new endoscopic innovations, adverse events associated with endoscopy, and natural history of chronic conditions. This project spans the interface of biomedical research and information technologies. CORI's success depends upon maintaining a consortium of practice-based clinicians who send data to the national repository. A large, diverse consortium allows the study of effectiveness of endoscopy in "real life" practice. In Phase I of the project, all clinical affiliates use a computerized report generator developed specifically for the project. In Phase II, interfaces will be created to capture endoscopic data from other computerized report generators, image management systems, and non-endoscopic data from electronic records while maintaining quality control and preserving patient privacy. These enhancements will enrich the data repository and enhance effectiveness research. The primary goal of this proposal is to use information technologies to enhance CORI's research mission through: Expansion of participation in CORI to users of commercial software, Incorporation of non-endoscopic data into the endoscopic database, Enhancement of consortium-building with novel methods of member communication, Acquisition of endoscopic images for research and validation of terminology.